Process for the coloration of cellulose ester and ether materials



Patented Sept. 19, 1933 PROCESS FOR THE COLORATION OF CELLU- LOSE ESTER A'ND ETHER MATERIALS George Holland Ellis and William Bertram Miller, Spondon near Derby, England, assignors to Celanese Corporation of America, a corporation of Delaware No Drawing. Application January 29, 1930,

This invention relates to the coloring of textile materials made of or containing cellulose acetate or other esters of cellulose, or made of or containing cellulose ethers.

The coloration of textile materials can be effected, as is known, by the oxidation thereon of various oxidizablearomatic amines. Full and fast black shades have long been produced on cellulosic materials in this manner. To obtain satisfactory results, particularly when employing aniline, it has usually been regarded as good practice not only to avoid the presence of free acid but to have part of the aromatic amine present in the free state; tendering of the fibres is also avoided thereby. When the coloration of materials made of cellulose esters or ethers is attempted in this way it is found that the oxidation of the arcmatic amine on the material does not proceed so readily as is the case on cellulosic materials.

It has now been found that the conditions requisite for the production of satisfactory colorations on cellulose ester or ether materials by the oxidation of aromatic amines, particularly aniline, thereon are essentially different from those which yield the best results in the case of cellulosic materials and that the coloration of cellulose ester or ether materials by this method is much facilitated by the presence of acid in considerably greater proportions than those commonly employed in the coloration of cellulosic materials by similar methods.

According to this invention colorations are produced on materials made of cellulose acetate or other cellulose esters, or made of cellulose ethers, by the oxidation thereon of aromatic amines in the presence of-mineral acid in quantity chemically equivalent thereto, there being present in addition a quantity of a substance having an acid reaction, for example a mineral or organic acid, or an acid salt, or a salt having an acid reaction, but preferably an organic acid.

The process is of particular advantage when it is required to color cellulose ester and ether materials by the oxidation thereon ofcomparatively difficultly oxidizable amines, for example aniline, but the invention is not limited to the use of such amines. In place of aniline there may be employed any other aromatic amine capable of yielding colorations upon oxidation on textile materials, e. g. l-naphthylamine, a diamino-diphenylamine, p aminodiphenylamine, dianisidine, benzidine, or tolidine, or a mixture of two or more of such aromatic amines.

In carrying the invention into effect the aromatic amine and equivalent quantity of mineral acid may conveniently be applied to the materials in the form of the mineral acid salts of the amine. The materials may, for example, be padded with a solution or liquor containing a mineral acid salt of aniline, e. g. the hydrochloride or nitrate, a substance having an acid reaction, e. g. acetic acid or a salt having an acid reaction such as aluminium chloride, and an oxidizing agent, for example a chlorate with or without oxidation catalysts such as salts of vanadium, copper, or iron. After padding and drying the materials may be aged and may then be chromed and soaped according to the usual methods. Full ungreenable black shades are obtained by oxidizing aniline in this manner on cellulose acetate materials.

The invention is not limited however to the application of the aromatic amine salt, acid, and oxidizing agent by padding, nor to the application of these materials in a single operation. For example they may be applied by printing or other means of local application or by a simple passage of the material through a bath containing them or they may be applied in succession by padding the material with, or passing the material through, two or more solutions each contain-' ing one or more of the necessary compounds- When dyeing cellulose ester or cellulose ether materials according to the above process, white or coloured pattern effects may be simultaneously produced thereon. 'White pattern effects for example may be produced on a black or coloured ground by local application, at an appropriate stage of the process, of a resist or discharge preparation, that is to say, a preparation consisting of or containing an agent which inhibits, either mechanically or chemically, the oxidation of the aniline or other aromatic amine or amines, for example a reducing agent or an agent which neutralizes acids or which substitutes organic acid for mineral acid, e. g. sodium formaldehyde sulphoxylate, zinc oxide, sodium or potassium acetate, or sodium sulphocyanide. The resist -or "discharge preparations may contain, in addition to the'agent which inhibits oxidation of the aromatic amine, suitable thickening agents to render them suitable for application by printing or other mode of local application. Thus white resist or discharge effectson-a dark ground may be obtained on cellulose'esteror ether materials by printing -or otherwise locally treating them with the resist or discharge preparation, drying, and thenapplying a solution containing an aromatic amine mineral acid salt, an

acid substance, and an oxidizing agent; or the latter solution may be applied first and the material dried and printed or otherwise locally treated with the resist or discharge preparation; upon ageing the material the oxidation coloration is only developed upon the parts which have not been treated with the resist or discharge preparation. Alternatively the order of the operations may be that described in U. S. patent application S. No. 383,977, filed August 6, 1929, that is to say the material may be impregnated with an oxidizing agent, printed or otherwise locally treated with a resist preparation comprising a reducing agent, then padded with a solutioncontaining a mineral acid salt of an oxidizable aromatic amine and free acid, and finally aged and finished in the usual manner. Colored pattern effects may be obtained in a similar manner by incorporating in the aforesaid resist" or discharge preparations dyestuffs which have affinity for cellulose esters or ethers and which are unafiected by the resist or discharge preparations or by the ageing and finishing processes.

Though the invention has been more particularly described with reference to the coloring of materials made of cellulose acetate it is also applicable to the coloring of materials made of other cellulose esters, for example cellulose form-- ate, propionate, or butyrate, or the products obtained by the treatment of alkalized cellulose with esterifying agents (e. g. the product known as 'immunized cotton obtained with p-toluenesulphochloride) or of cellulose ethers, for instance methyl, ethyl, or benzyl celluloseor the corresponding condensation products of cellulose and glycols or other polyhydric alcohols, or made of mixtures of two or more of these products.

The invention may also be applied to the dyeing or otherwisecoloring of materials containing one or more cellulose esters or ethers in admixture with a material or materials of another kind,

particularly animal fibres such as wool or natural silk. A material containing cellulose acetate and wool may for example be dyed in a solid black or other shade according to the process of the invention.

The invention is illustrated but not limited by the following examples:

Example 1 A fabric woven from celluluose acetate yarns is treated in a suitable padding machine with a pad liquor composed as follows:

The padded material, which is squeezed to hold about its own weight of liquor, is dried either in a hot fiue or on heated cylinders, after which it is given a passage through the "rapid ager for 5 minutes at 100 C. After ageing, the material is run through a bath of sodium bichromate, 5 gms. per litre, at 50 C. for two minutes, rinsed, soaped or further treated as desired or requisite. A good full black shade is thus obtained.

Example 2 A woven fabric composed of cellulose acetate is printed on a roller printing machine or by hand block with a four color design using four printing colors as follows:--

(a) Grams Gum arabic 1:1 4'70 Methylated spirit 50 Water 180 Sodium acetate 300 (b) Grams Rhodamine 6G powder (Color Index No. 752) 40 Methylated spirit 50 Water 160 Sodium acetate 1 300 Gum arabic 1:1 450 (C) Grams 3:3 dinitro 4:4 diamino diphenyl methane 20% aqueous paste 100 Methylated spirit 50 Water 100 Sodium acetate 300 Gum arabic 1:1 450 1000 (d) Grams 1:4 dimethyldiaminoanthraquinone 20% paste 100 Methylated spirit so 1 Water 100- Sodium' acetate 300 Gum arabic 1:1 450 The printed fabric, having been dried as usual, is treated in a suitable padding machine with the aniline black liquor described in Example 1, the fabric passing through the padding rollers without being drawn through the liquor. After drying the material is given a passage through the rapid ager and is then steamed in the cottage steamer for 'to 1 hour with steam at 5 lbs. pressure. The subsequent operations of 180 chroming and soaping are carried out as in Example 1, after which the fabric is further treated as desired or requisite. A pattern in white, red, yellow and blue on a black ground results.

Example 3 A fabric woven from cellulose acetate yarns is treated in a suitable padding machine with a pad-liquor composed as follows:---

Solution A Gram. Aniline hydrochloride 96 p-aminodiphenylamine hydrochloride 52 Glacial acetic acid 25 Water 227 Alcohol 100 Gum arabic 1:1: 200

Solution B Grams Sodium\chlorate 80 Cupric chloride 3 Water 217 Solutions A and B are mixed just before padding. The material is impregnated with this mixture, squeezed to hold its own weight of liquor and dried. It is then given a fiveminutes passage through the rapid ager after which it is chromed in a solution of sodium dichromate for 2 minutes at C., rinsed, soaped or otherwise treated as desired or requisite. A fast black results.

Example 4 A woven fabric "composed of cellulose acetate yarns is treated in a suitable pad mangle with a The material after padding so that it holds its own weight of pad liquor, is dried either in a flue with hot air or on heated drying cylinders and is then given a .passage of five minutes through the rapid ager at 100 C., after which it is rinsed and soaped or otherwise treated as desired or requisite. The cellulose acetate is thus colored a deep brown shade.

Example 5 A fabric composed of cellulose acetate yarns is padded in a 5% solution of sodium chlorate -and dried. It is then printed with a printing paste composed as follows:-

Grams Gum arabic 1:1 260 China clay 100 Zinc formaldehyde sulphoxylate 200 Water 440 The printed fabric is dried and steamed in the cottage steamer for 3 minutes at 5 lbs. pressure or in the rapid ager for an equivalent steaming. It is then padded in a solution of the following composition, being preferably passed straight to the squeezing rollers without previous immer- The material after padding is dried and aged in the rapid ager at 100 C. or steamed for 5 minutes in the cottage steamer. It is'finally washed ofi well and soaped. A white pattern on a black ground is obtained.

Grams Aniline 54 Hydrochloric acid 28 Tw Glacial acetic acid 15 Methylated spirit 60 Cupric chloride crystals 2.4 Gum arabic 1:1 90 Water 298.6

Patent is:--'

1. Process for the coloration of materials containing organic derivatives of cellulose, comprising oxidizing an aromatic amine thereon in the presence of a mineral acid in quantity at least sufiicient to form a salt with the amine and in the presence of an additional acid reacting substance.

p 2. Process for the coloration of materials containing organic derivatives of cellulose, comprising oxidizing thereon in the presence of an acid reacting substance an aromatic amine in the form of a salt of an inorganic acid.

3. Process for the coloration of materials containing organic derivatives of cellulose, comprising oxidizing aniline thereon in the presence of a mineral acid in quantity at least suflicient to form a salt with the aniline and in the presence of an additional acid reacting substance.

4. Process for the coloration'of materials containing organic derivatives of cellulose, comprising oxidizing aniline thereon in the form of a salt of an inorganic acid and in the presence of an additional acid reacting substance.

5. Process for the coloration of materials containing organic derivatives of cellulose, comprising oxidizing aniline thereon in the form of a salt of an inorganic acid and in the presence of an organic acid.

6. Process for the coloration of materials containing cellulose acetate, comprising oxidizing thereon in the presence of an acid reacting substance, an aromatic amine in the form of a salt of an inorganic acid.

7. Process for the coloration of materials containing cellulose acetate, comprising oxidizing aniline thereon in the presence of a mineral acid in quantity at least sufiicient to form a salt with the aniline and in the presence of an additional acid reacting substance.

8. Process for the coloration of materials containing cellulose acetate, comprising oxidizing aniline thereon in the form of a salt of an inorganic acid and in the presence of an additional acid reacting substance.

9. Process for the coloration of materials made of or containing cellulose acetate, comprising oxidizing aniline thereon in the presence of a mineral acid .in quantity at least sufficient to form a salt with the aniline and in the presence of an organic acid.

10.- Process for the coloration of materials containing cellulose acetate comprising oxidizing aniline thereon in the form of aniline hydrochloride and in the presence of acetic acid.

11. Process for the coloration of materials containing organic derivatives of cellulose which comprises oxidizing aniline thereon with the aid of a chlorate in the presence of a mineral acid in quantity at least suflicient toform a salt with the aniline and in the presence of an additional acid reacting substance, the color formation being effected by ageing or steaming.

' 12. Process for the coloration of materials made of or containing cellulose acetate, which comprises oxidizing aniline thereon with the aid of a chlorate in the presence of a mineral acid in quantity sufiicient to form a salt with the aniline and in the presence of an organic acid the color formation being effected by ageing or steaming.

GEORGE HOLLAND ELLIS. WILLIAM BERTRAM MIL ER. 

